Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

DIY: Do It Yourself Post here to share or improve your wrench turning skills! All BMW E46 DIY tips, tales, and projects discussed inside. Learn to work on your car and know the right BMW parts you will need!

(modified version of dubplaya’s install guide)
1. Place your front wheels on ramps or jack stands.
----- Jack stands (especially for lowered vehicles): Use your OEM jack (or Hydraulic jack) to jack up either side of your car using the front jack point underneath the side skirt.
----- Now locate the center jack point underneath (There should be a circle indentation located in the front of the car right in the middle).
----- Once you find it use your second jack to lift the front end high enough in order to place the jack stands securely underneath the front jack points (underneath the side skirt)

3. Remove the secondary air pump (three 10mm bolts). There’s two on the top and one on the bottom. Remove the connected plug.

(courtesy of Minnoe07)

**** At this point you can remove and label the top two 02 sensors (22mm) you see above with blue/masking tape (ex. L1, L2, R1, R2)
4. Remove the underbody tray cover (six screws with Phillips head). After you remove it, slide the cover towards the rear of the car.

(courtesy of Minnoe07)

5. Remove the metal subframe brace (eight 16mm bolts)

(courtesy of Minnoe07)

6. Support the bottom of the motor with a jack and 2x4
7. Unbolt the connecting ground wire from the car coming from the engine mount (13mm)

(courtesy of Minnoe07)

8. Unbolt the passenger side engine mount (four 13mm bolts)

9. Remove the bolt holding the passenger engine mount (16mm)

10. Remove Passenger Side engine mount.**** At this point, you can label and remove the remaining two 02 sensors (22mm) you see below on the headers (ex. L1, L2, R1, R2)

11. Remove the OEM headers and gaskets(sixteen 11mm nuts, eight on each header)

----- You will be spending most of your time here at this point.
----- Start first on the header (longest one) closest to the front of the car.

**** At this point, you can take a break to soak the nuts and bolts w/ WD-40 removing the rust.

(courtesy of Minnoe07)

12. Install the new OEM gasket and aftermarket headers.

----- Start with the header closest to the front of the car because it will be easier to maneuver the second header in.
----- Make sure you apply Threadlocker or Loctight on the last couple of millimeters of thread before tightening.
----- Be sure to have a paper towel (or Q-tips) handy to wipe off any excess that forms around the hex nut because the product will harden. Do not get any of this stuff in your hair or eyes.

13. Re-install the 02 sensors and spark plug non-foulers in the correct locations

14. With the passenger engine mount, use a pair of pliers or adjustable wrench to remove the excess heat shield. This will help with header clearance.

15. Reverse steps 10 thru 1

----- If you’re having trouble getting the engine mount back in, start with one end (the side w/ four bolts) coming in towards the front of the car then turning it.
----- If you’re having trouble bolting the engine mount back on, start with two bolts in at first tightening them down one by one. Be sure not to strip any threads.
----- After you re-install the passenger side engine mount and ground wire. Start up the car to check and see if you have any leaks.
----- You will see some smoke rise off the headers at first from the Threadlock/Loctight, which will burn off after a few minutes.

I was speading this stuff like a fat kid spreading cream cheese on a bagle

ps. got these too

Need two
Need two

oh while i was at it I also replaced the motor mount of the passenger side...but got lazy and tired and still need to do the driver side...GD know when it will be the next time i take of the motor mount braket!

I didnt get Spark Plug Non-Foulers...i was just going to wing it and get teh AA chip

I didn't see it written, but it is highly advised that one runs the car to full operating temperature for a while, then re-tighten the bolts. Metal will expand at high temperatures and cause the bolts to loosen up. So don't miss this step.

Im going to a muff shop to get him to cut and weld me flanges in the correct place. Has anybody else had a problem with this on their ebay headers? I bet if i would have tried what autobot said i could have gotten it to work, but i am too tired at this point.

Im going to a muff shop to get him to cut and weld me flanges in the correct place. Has anybody else had a problem with this on their ebay headers? I bet if i would have tried what autobot said i could have gotten it to work, but i am too tired at this point.

You must of received the wrong set of headers. There are differences between the 323/328 and the 325/330 headers, and it's in the flanges. It's not a big deal if you're willing to get a shop to cut/weld. Who was the seller you bought from?

You must of received the wrong set of headers. There are differences between the 323/328 and the 325/330 headers, and it's in the flanges. It's not a big deal if you're willing to get a shop to cut/weld. Who was the seller you bought from?

They are the right headers. My cousin bought them and he recieved the wrong set for his car (330) so he sold those to me (323) and ordered another set. I know I have to right one, It is just that the flanges where the exhaust meets the header is off a few mm's.

Im going to a muff shop to get him to cut and weld me flanges in the correct place. Has anybody else had a problem with this on their ebay headers? I bet if i would have tried what autobot said i could have gotten it to work, but i am too tired at this point.

I had the same problem as well. It was slightly off on one of the pipes by a few mm or so. Take it to an exhaust shop and they should be able to line it up for ya.

I took mines to Midas and they told me that the bolts were on backwards?? (funny that I had tried them both ways and it didn't work) but they didn't charge me a dime. It's good to know a few people

I didn't see it written, but it is highly advised that one runs the car to full operating temperature for a while, then re-tighten the bolts. Metal will expand at high temperatures and cause the bolts to loosen up. So don't miss this step.

Awesome write-up BTW

yea...i drove a few miles and went back to the nuts...yea a few of them were not tight at all.

wearing long sleeve and a workers glove...didnt get burned till my sleeve rolled up a little and i touched the header with my wrist...

ouch. but it def. helps to get back and check the install after a warm engine

Nice. I do appreciate the write up, it helped me and my friend get this done in under 6 hours from the minute i popped the hood.

Problems we came across..

my car has 167k miles so the bolts connecting to the flanges were severely rusted to the point we had to cut them off.

PLEASE dont forget to label the 02 sensors.. luckily I got them back in correct order first time.. after 20 minutes of staring and trying to use logic.

buy the oem gaskets, i got mines for 25ish bucks..each.. mine came with individual gaskets, and it would have been a headache trying to get them in... good thing i read this thread..

I'm going to double check the torque on the bolts tomorrow after running if a few times.

I don't know if you guys header flanges are the same, but mine had thread on the flanges of the header, so no need for nuts.. the bolts were installed the other way around so that the bolt starts on the mid pipe side of the exhaust, the head of the bolt is on the mid pipe flange and it's screwing the header flanges into the midpipe flange.. dunno if it make sense.. but normally the bolt starts on the header side, with a nut on the midpipe flange side and clamps them together.

Please have plenty of PB blaster/WD 40 handy along with a flex head/swivel socket handy...

(modified version of dubplaya’s install guide)
1. Place your front wheels on ramps or jack stands.
----- Jack stands (especially for lowered vehicles): Use your OEM jack (or Hydraulic jack) to jack up either side of your car using the front jack point underneath the side skirt.
----- Now locate the center jack point underneath (There should be a circle indentation located in the front of the car right in the middle).
----- Once you find it use your second jack to lift the front end high enough in order to place the jack stands securely underneath the front jack points (underneath the side skirt)

3. Remove the secondary air pump (three 10mm bolts). There’s two on the top and one on the bottom. Remove the connected plug.

(courtesy of Minnoe07)

**** At this point you can remove and label the top two 02 sensors (22mm) you see above with blue/masking tape (ex. L1, L2, R1, R2)
4. Remove the underbody tray cover (six screws with Phillips head). After you remove it, slide the cover towards the rear of the car.

(courtesy of Minnoe07)

5. Remove the metal subframe brace (eight 16mm bolts)

(courtesy of Minnoe07)

6. Support the bottom of the motor with a jack and 2x4
7. Unbolt the connecting ground wire from the car coming from the engine mount (13mm)

(courtesy of Minnoe07)

8. Unbolt the passenger side engine mount (four 13mm bolts)

9. Remove the bolt holding the passenger engine mount (16mm)

10. Remove Passenger Side engine mount.**** At this point, you can label and remove the remaining two 02 sensors (22mm) you see below on the headers (ex. L1, L2, R1, R2)

11. Remove the OEM headers and gaskets(sixteen 11mm nuts, eight on each header)

----- You will be spending most of your time here at this point.
----- Start first on the header (longest one) closest to the front of the car.

**** At this point, you can take a break to soak the nuts and bolts w/ WD-40 removing the rust.

(courtesy of Minnoe07)

12. Install the new OEM gasket and aftermarket headers.

----- Start with the header closest to the front of the car because it will be easier to maneuver the second header in.
----- Make sure you apply Threadlocker or Loctight on the last couple of millimeters of thread before tightening.
----- Be sure to have a paper towel (or Q-tips) handy to wipe off any excess that forms around the hex nut because the product will harden. Do not get any of this stuff in your hair or eyes.

13. Re-install the 02 sensors and spark plug non-foulers in the correct locations

14. With the passenger engine mount, use a pair of pliers or adjustable wrench to remove the excess heat shield. This will help with header clearance.

15. Reverse steps 10 thru 1

----- If you’re having trouble getting the engine mount back in, start with one end (the side w/ four bolts) coming in towards the front of the car then turning it.
----- If you’re having trouble bolting the engine mount back on, start with two bolts in at first tightening them down one by one. Be sure not to strip any threads.
----- After you re-install the passenger side engine mount and ground wire. Start up the car to check and see if you have any leaks.
----- You will see some smoke rise off the headers at first from the Threadlock/Loctight, which will burn off after a few minutes.

Hello dirsh it appears that you have not posted on our forums in several weeks, why not take a few moments to ask a question, help provide a solution or just engage in a conversation with another member in any one of our forums?